rock wall, glue it or egg crate?
 

I found a thread regarding gluing live rock to the back of the tank with epoxy or something. Now that I need to find the info, I can't find the thread! My tank's back wall is nasty (prior owner glued mirrors to part of it, his fix to hide the overflow???? and the back will be scratched up after mirror removal). I would like to glue live rock to the back of it, how would I go about doing this? I understand silicone lets go after a period of time. Can this be done using rock that is wet or would I have to dry my live rock out before gluing it? I am not opposed to egg crate as a frame to put rock on but I am afraid of things getting stuck behind and dying. This may let me be more creative, I can use foam to create caves etc. and use electrical ties to strap live rock (may have to drill holes in some so they sit properly)

What is the pros and cons of each method?

1) gluing rock directly on back of tank

or

2) using egg crate as a structure and get creative from there.

The thread is in the DYI section on RC. Everyone seems to prefer attaching thier LR to eggcrate then filling in the gaps with pond foam and aragonite sand. Finally attaching the whole thing to the back wall using silicone.

go with the eggcrate. there is a huge thread about it on rc. looks good from what i have seen. another option is to paint your back pane black, scratches shouldnt show.

http://www.canreef.com/vbulletin/showthread.php?t=45915
i built a rock wall in my cube, its in the thread somewhere

This is the thread that I had read before, thanks! Awesome tank! Do you have any regrets doing the rock wall?

The egg crate wall is certainly the easier method. I am a little worried about algae build up. It would be hard to clean the argonite sand on the wall. Does anyone have experience with this?

I built a wall out of eggcrate and cement. Worked out great. You need architectural cement, you can see the results inmy photo gallery
def suggest going with the eggcrate however you choose to fixthe rock to it.

Did you have to cure the cement? does the cement effect the ph?

Yes, you have to cure the cement under water for about 2 months, but you can't match the look with zip ties or glue. Does not impact my ph at all. If you want more details onhow I built it whip me a pm.

I did the same for my tank. I just used regualr cement and mixed up a batch of aragacrete (cement, aragonite sand, crushed coral). After a good long cure, it went in the tank and was soon covered with growth making it look totally natural.

I siliconed my rock to the back wall cut them flat on a tile saw and let them dry. So far it has just been fine.